TEKKEN 4 and Street Fighter EX3 question
 

I have back-ups of the two games above. I wanna know why not all characters are available to play (in the place of them there question marks). It's very weirdo cause before it seemed that they were appearing and now they are not. Can anyone explain me why it happens?

It is most likely because a file was deleted or writen over on your memory card.

Yep.... Sounds like your memory card got erased.... The backup shouldn't have anything to do with it.....
Check from the browser screen and see if your memory card has a Tekken 4 or EX3 file on it....

Thank you guys! That's it! Some weeks ago I realized that my memory card was almost totally full (I bought my PS2 from a friend) and I decided erasing some files and I didn't know that the status of the game characters were stored there... And now I think that I have to defeat these characters again in order to bring them back, right?

Correct